The present invention is concerned with devices which generate ozone for numerous industrial applications such as oxidation of cyanide in electroplating waste, decolorization of dye stuffs, purification of refining waste water, disinfection of seawaters, treating paper for printing, water purification, odor control in sewage treatment and sterilization. Ozone generators commonly used today employ the corona discharge principle. This technique utilizes a high tension electrode and a ground electrode mounted in a spaced relation with a vitreous dielectric member covering one of the electrodes. The electrodes are connected to an electric power source to set up an electrostatic field or corona in the space between the dielectric material and one of the electrodes. An oxygen-containing gas (air or oxygen) is then passed through the space between the dielectric material and electrode.
Creation of the electric discharge field requires considerable expenditure of electrical energy. More than 80% of the electrical energy applied to the electric discharge field is converted to heat and, if this is not quickly removed from the electrostatic field, it will cause rapid decomposition of the product ozone back to oxygen. The rate of this reversal reaction increases rapidly above 35.degree. C. and is almost instantaneous at temperatures in the range of 200.degree. C. The dielectric member is generally in the form of a solid vitreous material such as glass, fused quartz or ceramic. Heat builds up in the vitreous dielectric material so that the material generally operates at temperatures approaching the critical 200.degree. to 250.degree. C. range. Proper cooling of the ozone generator is therefore critical to maintaining a practical operating efficiency and consistent yields of ozone. The temperature is usually maintained at approximately 100.degree. to 150.degree. C. by circulating air or oil along the back of the electrodes in order to cool the dielectric member. The vitreous materials are also very fragile requiring special handling both in manufacture as well as use.